1. Technical Field of the Invention
The present invention relates to radio frequency communication systems, and more particularly, to the transmission of data between transceiver/transcoder pairs.
2. Description of Related Art
Prior art digital cellular systems employing time division multiple access (TDMA) carriers offer distinct advantages over analog cellular systems in both system capacity and electrical performance. In a TDMA system, two or more channels of information are transmitted over the same link by allocating a different time interval for the transmission of each channel. For RF digital cellular systems, each time interval (message channel) contains coded speech (or data) for one traffic channel (voice channel).
Common to all RF digital cellular systems is transcoding which essentially transforms high bit rate speech data into high quality synthesized speech at low bit rates. Transmission of the transcoded data to a mobile station occurs after transmission of the data from a transcoder to a transceiver unit. The interconnections between the transcoders and transceivers utilize a great deal of the system resources, and the ability to more efficiently transfer this data between the transcoder and transceiver would greatly benefit the providers of cellular services.
One scheme utilizes specialized compression and decompression equipment associated with the transceiver and transcoder to compress information from a plurality of message channels for transmission on a single TDMA information block. The compression equipment inserts synchronization into the information block and conveys the block in a timeslot between the transcoder and the transceiver. This information may then be transmitted over a radio carrier frequency. This system involves a great deal of complexity due to the specialized compression/decompression equipment at the transcoder and transceiver and the requirements for synchronizing the end points of the compressed data block into which the compressed message channels are located. A more simplified method for reducing transmission requirements between a transcoder and transceiver would be greatly beneficial.